Papermaking machine shaping cylinder having trapezoidal-shaped peripheral trough-like boxes

ABSTRACT

A PAPERMAKING MACHINE SHAPING CYLINDER WHICH INCLUDES A PLURALITY OF TRAPEZOIDAL-SHAPED TROUGH-LIKE BOXES AT THE PERIPHERY WHICH ARE OPEN TO A WIRE MESH CIRCUMFERENTIALLY DISPOSED ON THE CYLINDER OVER THE BOXES. THE BOXES ARE CONNECTED BY RINGS TO TWIN WHEELS SPACED APART FROM ONE ANOTHER, AND WHICH ARE THEMSELVES CONNECTED TO THE SHAFT OF THE CYLINDER. TWO DISTRIBUTOR MEMBERS ARE URGED AGAINST OPENINGS IN THE RINGS SO AS TO COMMUNICATE EITHER COMPRESSED AIR OR VACUUM TO THE INTERIOR OF THE BOXES IN A FASHION TO ADHER FIBERS FROM A SLURRY ONTO THE WIRE MESH AND THEN TO TRANSFER THE FORMED FIBROUS SHEET ONTO A FELT CONTACTING THE CYLINDER. A SCREW-THREADED BUSH MOUNTED ON TWO ALIGNED PINS ALLOWS A DISPLACEABLE SEGMENT OF THE CYLINDER PERIPHERY TO MOVE TOWARD AND AWAY FROM THE SHAFT TO FACILITATE ASSEMBLY AND DISASSEMBLY OF THE MESH.

Oct. 3, 1972 zzo 3,695,996

PAPERMAKING MACHINE SHAPING CYLINDER HAVING TRAPEZOIDAL-SHAPEDPERIPHERAL TROUGH-LIKE BOXES Filed Feb. 12, 1970 3 Sheets-Sheet 1 Tm'RPREssuRE SOURCE VACUUM SOURCE l L/-\ A J IXVEXTOR BY J 7 61/6/15164w; fizzle a 9AM) flaws/e vv/eA svs Oct. 3, 1972 FREZZOTT] 3,695,996

PAPERMAKING MACHINE SHAPING CYLINDER HAVING TRAPEZOIDAL-SHAPEDPERIPHERAL TROUGHLIKE BOXES Filed Feb. 12, 1970 3 Sheets-Sheet z Oct. 3,1972 A. FREZZOTTI 3,695,996

PAPERMAKING MACHINE SHAPING CYLINDER HAVING TRAPEZOIDALSHAPED PERIPHERALTROUGH'LIKE BOXES Filed Feb. 12, 1970 s Sheets-Sheet s dig. 5

ll ii United States Patent Int. Cl: DZlf 1/60 US. Cl. 162-273 ClaimsABSTRACT OF THE DISCLOSURE A papermaking machine shaping cylinder whichincludes a plurality of trapezoidal-shaped trough-like boxes at theperiphery which are open to a wire mesh circumferentially disposed onthe cylinder over the boxes. The boxes are connected by rings to twinwheels spaced apart from one another, and which are themselves connectedto the shaft of the cylinder. Two distributor members are urged againstopenings in the rings so as to communicate either compressed air orvacuum to the interior of the boxes in a fashion to adher fibers from aslurry onto the wire mesh and then to transfer the formed fibrous sheetonto a felt contacting the cylinder. A screw-threaded bush mounted ontwo aligned pins allows a displaceable segment of the cylinder peripheryto move toward and away from the shaft to facilitate assembly anddisassembly of the mesh.

This invention relates to an improvement in the shaping cylinders forthe continuous machines used in the manufacture of paper, paperboards,nonwoven fabrics, asbestos-cement and the like.

As is known, the machines of the continuous type for paper manufacturecomprise one or more manufacturing units, comprising a container to holda suspension of fibres in water, and a hollow cylinder, which ispartially dipped in the suspension and coated by a wire mesh or the likeand is rotated about a horizontal axis. The water in the container oozesthrough the meshes of the wire gauze or net, whereas the fibres stickthereto to form a thin layer. Such a layer, as it reaches the top of thecylinder, adheres to the lower surface of a collecting felt arrangedtangentially with respect to said cylinder and adhering to a portionthereof, thrust thereagainst by a pressing or setting roller.

In the case of a machine having a plurality of manufacturing units,there is a succession of paper layers, called castings which aresuperposed in said collecting felt until reaching the expectedthickness.

It is apparent that in machines of the kind referred to above in orderthat adhesion of the sheet to the lower surface of the collecting feltmay be achieved, the sheet should exhibit no discontinuity, especiallyin a direction which is transversal to the drum.

An object of the invention is to provide a shaping cylinder by means ofwhich it is possible to manufacture a continuous paper layer cutaccording to scripts, figures or drawings whatsoever. Such a cut layercan be incorporated between two continuous layers, either of the same orof different colors, so as to obtain a watermark paper which can be of acolor other than that of the sheet, or can be applied on a continuouslayer, either alone or in combination with other cutout layers so as toobtain an end product composed by paper (or paperboard) reproducing thedesired figures or symbols, in one or more colours.

According to the invention a device is provided, wh ch consists, incombination, of a horizontal shaft carrying 3,695,996 Patented Oct. 3,1972 at least two wheels staggered and integral with said shaft, atleast two ring gears having radial openings afllxed to the peripherythereof, a set of boxlike compartments having a trapezoidalcross-sectional shape and arrayed the one alongside the others andintegral with said ring gears, and arranged along the generating linesof the cylinder, with the larger base open and wrapped by a wire mesh,and the lesser base closed, a pair of holes formed at the ends of eachboxlike compartment in registry with the openings of said rings, and apair of fixed distributors which slide in a sealtight manner against theinner edge of said rings, so as to establish an air pressure or anegative pressure in the interior of said boxlike compartments, as afunction of their position during the rotation of the cylinder.

Said distributors consist of two shoes in the form of arcs of a circle,having a set of radial chambers and supported by a rocker mounted idlyon the cylinder shaft.

Still according to the invention, said radial chambers are formed, each,by a fitting for a duct which opens into a source of compressed air orof negative pressure, according to the position of the shoesaforementioned so as to cause the sheet fibres to adhere to said wiremesh and to cause the sheet to be released from the mesh, the resultbeing the adhesion of the sheet to the collecting felt.

Still according to the invention, one or more portions of the wire meshare coated with a varnish or the like, according to a preselectedpattern, to prevent the formation of the fiber layer in that portion orportions so as to obtain a cut-out sheet according to the preselectedpatterns.

This invention will now be described with reference to the accompanyingdrawings which show, by way of illustration without limitation, apreferred embodiment of the invention.

In the drawings:

FIG. 1 is a front elevational view of the device, partly in section,along a plane perpendicular to the axis of rotation.

FIG. 2 is a side elevational view, in section along the Vertical planepassing through the axis of rotation.

FIG. 3 shows the detail of the removable sector.

FIGS. 4 and 5 shows the cross-sectional views, taken along the planesA-A and B-lB of FIG. 3.

Referring to FIGS. 1 and 2, the numeral 1 indicates the horizontalshaft, mounted for rotation in journals (not shown), which receives itsrotary drive from any drive-transferring mechanism, or is directlydriven by the collecting felt. The shaft 1 dips in a manufacturing unitor tub containing a suspension of fibres in water whose outer level isshown at 2 in FIG. 1 whereas 2 is indicative of the inner level.

To the shaft 1 are keyed two twin wheels 3, appropriately spaced apartfrom one another, to which are afiixed by screws 4 the circular rings 5equipped with a set of radial openings 6 and integral with the frontcircle 7 having a rim 8. To the rings 5 are afiixed the boxes 9 having atrapezoidal cross-section, which are arranged according to thegenerating lines of the cylinder and mounted on said rings by the screws10 and 11 (FIG. 5). The boxes 9 are placed the one alongside the others(see also FIG. 3), and comprise the two sidewalls 12, the bottom wall 13and the transversal sheet metal walls 14 whose outline is slightlyarcuate. The boxes. 9 are open at their tops and a mesh 15, formed by awire mesh or another mesh of an appropriate material, is mounted tautthereon.

On the inner edge of the rings 5 are mounted two distributor members 16in the form of a fixed shoe, having an angular width of a preselectedamplitude. Each distributor 16 is supported by a rocker 17 having a hub18 mounted idly on the shaft 1 and is resiliently urged against saidedge of the foraminous ring 5 by springs 19 located about the guidingposts 20.

The two arcuately shaped distributors 16 comprise segments 21 havingsealing gaskets 22, between said segments a set of radial chambers 23being formed, which communicate via first openings 23 with the openings6 of the ring 5 and thus with the interior of the boxes or tubs 9through the openings 35. The radial chambers 23 of the distributor 16have a second opening or fitting 24 for the connection with a source ofcompressed air or a vacuum source, as will be more detailedly set outhereinafter and as shown in FIG. 1.

Over the wire mesh 15, a continuous collecting felt 25 is caused toslide tangentially and is pressed against the cylinder by a pressureroller 26.

In order to facilitate the assembling and disassembling operations ofthe mesh 15, the wheels 3 have a sector 27 which can be displacedtowards the centre of the cylinder by the agency of the screw-threadedbush 2.8 which is active against the pins 29. In order that such adisplacement may be allowed (FIGS. 3 and 4) the set of boxes 9encompassed by said sector have at their sides two sets of pins 30carrying the tongues 31 aligned with the blades 14. The pins 30 arecarried by the strips 32 having set screws 33. As seen in FIG. 4, thepins 30, as regards the portion concerning the ring 5, are directlyscrewed on the same ring. Alternatively, any appropriate sealingconnecting means may be utilized here.

The operation is as follows. Assuming that the directions of rotationare those of the arrows of FIG. 1, a negative pressure is applied to thechambers 23 of the distributor 16 which are located between the immersedportion of the cylinder and the point of contact between the roller 26and the felt 2 5, whereas compressed air is fed to the chambers 23 lyingbeyond said point of contact. The result is that the fibres contained inthe suspension 2 adhere to the wire mesh 15 down to the underside of theroller 26, whereupon, as this point has been overtaken, the sheet formedby said fibres is urged by the effect of compressed air so as to adhereto the lower face of the collecting felt 25 with which it goes ontowards the further processing operations.

If one or more areas, shaped according to any preselected areas in theshape of any pattern or inscription, are clogged or waterproofed on thewire mesh 15 by means of a varnish or any other suitable means, no sheetformation takes place in said areas, so that a continuous cutou sheet isobtained, which is empty in said areas and is separated from the mesh 15and adheres to the lower face of the felt 25 by virtue of the action ofthe compressed air which, from the chamber 23, passing through theopenings 6 of the ring, reaches the interior of the boxes 9 as thelatter pass over the distributor 16. To regulate the action of thenegative and the positive pressures in the distributor 16, the lattercan be rotated about the shaft 1, either manually or by any othercontrol member (not shown).

To do away with fibres which may possibly have adhered to the cloggedareas of the wire mesh 15, water sprays are provided, emerging from oneor more sprinklers 34.

With a cylinder such as described above, it is possible to operate at aspeed which is definitely higher with any kind of manufacturing unit.

Of course, with a unidirectional manufacturing unit which alreadypermits of high speeds, said speeds can obviously be doubled, wellfelted sheets being always the result. In addition, as compared with aconventional cylinder, it is possible to obtain much higher thicknesses,so that the cylinder according to the invention lends itself in aspecial manner for continuous machines for the production of paperboardsor Bristol boards.

With more than one cylinder, as described above, or with a conventionalcylinder and a plurality of cylinders or the kind described herein,applied to a continuous papermaking machine, a wide variety of specialpapers can be manufactured as a continuous sheet, a result which cannotbe achieved with the usual machinery.

With a continuous machine having two manufacturing units, the first ofwhich has a conventional shaping cylinder and the following unit has ashaping cylinder with sucking and blowing boxes, a special compositepaper can be manufactured, since on the first shaping cylinder (eitherconventional or special) which forms a continuous sheet of the width ofsaid cylinder, the sheet in question can be printed during thelamination with scripts or patterns which have been formed, either as apositive or negative image, on the mesh of the special cylinder.

If the cutou sheet made by the special cylinder has a colour other thanthat of the sheet formed by the first cylinder, after the lamination asingle sheet of paper is obtained, which has faces of different colorbut reproduces in one color only the letters, numerals or patternsreproduced on the mesh of the second shaping cylinder.

With a machine equipped with a conventional shaping cylinder and acylinder according to this invention, it is possible to manufacturecontnuously blank envelopes already fitted with linings of a differentcolor, by applying breaking lines on the first sheet which delimits theshape of the envelope and obtaining the pattern of the lining as apositive image, so that the latter, upon lamination, with an appropriatesynchronization of the two shaping cylinders, may go to be united in theexact position where the lining should be in an envelope.

With a machine having three manufacturing units, the first and the thirdof which are equipped with conventional cylinders whereas the second,which is at the center, has a sucking and blowing cylinder, by causingthe central cylinder to reproduce patterns of a color other than thoseof the other two sheets, it is possible to obtain, upon lamination, asingle sheet with internal scripts or patterns of a different colour.These papers are extremely useful for safety purposes, as it generallyoccurs with papers for banknotes and the like.

If in the subject machine the gauze is punched to obtain a watermark andthe punched portion is delimited by a varnish, one obtains, uponlamination, a sheet of paper which internally contains a water-markwhose color can be other than that of the remainder of the sheet.

Such a result could be obtained heretofore only by manual procedures: bythe present invention this can be obtained as a continuous operation, sothat a craftsmanlike work can now be effected on an industrial scale.

If the machine, instead of a single sucking and blowing cylinder has twoof them, that is the second and the third, both synchronized with oneanother, it would be possible to obtain on the second cylinder thepunching defimited by a varnish whereas the third could have varnishedonly the portion occupied by the punching in the second cylinder, sothat, upon lamination, there is a sheet of paper which can be, byproviding three batches of different colors, of a single color on asurface, whereas the other surface has another color, a third colorbeing provided by the watermark which coincided, on account of thesynchronization, with the empty space provided in the third shapingcylinder.

If the machine had three shaping cylinders, all three of the sucking andblowing type so that in the two lateral shaping cylinders thenon-formation of the sheet is caused to coincide, the result would be asingle watermarked sheet which could have, by properly coloring thebatches, the watermarked sheet with a color different from that of theremainder of the sheet, well visible on the two surfaces.

Finally, by resorting to the already illustrated principle, with acontinuous machine having as many manufacturing units as the color onedesires to reproduce, on the first sheet, formed also by a conventionalshaping cylinder, it is possible to laminate fragments of sheets ofdifferent color which could be properly selected so as to reproduce anymulticolored pattern.

This invention has been described with reference to a preferredembodiment, being it understood that modifications and changes can beintroduced therein without departing from the scope of the subjectinvention.

The embodiments of the invention in which an exclusive property orprivilege is claimed are defined as follows:

1. A shaping cylinder for machines for manufacturing paper products,comprising: a horizontal shaft; two wheels carried on said shaft andspaced apart from each other, each wheel having an arcuate displaceablesegment radially movable toward and away from said shaft; two ringshaving radial openings fixed to the periphery of said wheels; aplurality of open trough-like members, having a trapezoidal crosssection with the larger base open and smaller base closed, disposed oneadjacent another on the circumference of and along the lines ofgeneration of said cylinder, said trough-like members being connected atopposite ends to said rings; sealing means connecting a first group ofsaid plurality of troughlike members disposed on said displaceablesegment to the remaining plurality of trough-like members disposed onsaid cylinder; an opening defined in each end portion of saidtrough-like members in registry with said radial openings in said rings;a wire mesh circumferentially disposed on said cylinder over the openbases of said trough-like members; moving means for moving each saiddisplaceable segment toward and away from said shaft to facilitateassembly and disassembly of said mesh on said cylinder; two arcuatelyshaped distributor members; means for mounting said distributor membersin sealed sliding contact with the inner surface of said rings; aplurality of generally radial passageways formed in said distributormembers, each of said passageways having first and second openings, saidfirst openings being in registry with corresponding ones of said radialopenings; and supply means supplying positive and negative air pressuresto said passageways, said supply means being disposed in registry withsaid second openings.

2. A cylinder according to claim 1, wherein said movable means comprisesa screw-threaded bush mounted on two aligned pins carried by saiddisplaceable segment and a hub idly mounted on said shaft, respectively,to control displacement of said displaceable segment toward and awayfrom said shaft.

3. A cylinder according to claim 1, further comprising a series oftransversal blades carried by said plurality of trough-like members,said blades having an arcuate shape corresponding to the curvature ofsaid cylinder wherein said mesh rests on said blades.

4. A cylinder according to claim 3, wherein said sealing means comprisestwo longitudinal strips having sealed gaskets.

5. A cylinder according to claim 4, wherein said 1ongitudinal connectionstrips include a set of pins having, at their upper ends, tongues whichare aligned with said blades.

References Cited UNITED STATES PATENTS 2,991,218 7/1961 Cirrito et a1.162-357 X 3,111,454 11/1963 Tucker et al 162-357 X 577,070 2/1897Sandham 162--DIG 1 3,291,682 12/1966 Hellstrom 162-357 2,669,910 2/1964Trotman 162-357 S. LEON BASHORE, Primary Examiner R. H. TUSHIN,Assistant Examiner US. Cl. X.R. 162-200, 335, 357

